cvs commit: src/sys/libkern mcount.c
brde at optusnet.com.au
Wed Jun 13 08:48:01 UTC 2007
On Tue, 12 Jun 2007, Kip Macy wrote:
> On 6/12/07, Bruce Evans <bde at freebsd.org> wrote:
>> bde 2007-06-13 06:17:48 UTC
>> FreeBSD src repository
>> Modified files:
>> sys/libkern mcount.c
>> Unbreak high resolution profiling a little: use dummy asms to prevent
>> timing loops being optimized away.
>> Once apon a time, gcc promised not to optimize away timing loops, but
>> gcc started optimizing away the call to a null function in the timing
>> loop here some time between gcc-3.3.3 and gcc-3.4.6, and it started
>> optimizing away the timing loop itself some time between gcc-3.4.6
>> and gcc-4.2.
> Will this fix the hang on boot that I saw earlier today?
No. It's unlikely that you even configure profiling.
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